Hi, so I recently started my new pc build with a ryzen 5900x using this mobo and I need to flash the latest bios for the board to be compatible. I originally put the whole PC together but got Q-Code number 2 on start-up which means "AP initialisation before microcode loading" im relatively sure this was because the cpu wasn't compatible with the current bios but feel free to correct me if wrong.

Now because I don't have another previous gen AM4 CPU im going to need to use the bios flashback tool on my mobo which is fine and dandy but that doesn't appear to work either and there seems to be little to no troubleshooting guides for this dodgy feature online so I came here to ask you good folk if there is anything that im missing here in the flashback process or anything I can try to make it work.

So far I have tried:

• Cleaning the drive and wiping everything on it as per a user guide on the ROG forums to make sure there is nothing left as traditional windows format won't do the job

• Using a usb under 32gb (mine is 8gb) and formatting as fat32

• Downloading the latest bios from the official asus page for my mobo and loaded the renamed .CAP into the root of my usb

• Unplugged and removed absolutely all cables/headers/io connections from the mobo so it was just the 24pin main power on standby and the usb plugged into the "BIOS" labelled USB port on the back

• I then attempted to load the new BIOS onto the mobo by switching the psu on and holding the "BIOS" button for 3 seconds however every single time I try it flashes 3 times and then turns into a solid light that just stays there indicating that it can't read the USB/File?

I don't understand as it seems im meeting all the requirements for this to go smoothly but the board won't detect anything from the USB at all. If anyone could provide a hand I would really really appreciate it as im at a loss for words and I don't know what to do

There is a new BIOS that has just been posted for the Crosshair VIII Hero (Wi-Fi), as well as the other Crosshair VIII boards. This BIOS updates AGESA to V2 PI 1.0.8.0. In addition to letting other Crosshair VIII owners know of the update, I would also like to know if anyone here that is using this board and running a GNU/Linux distribution has a "no irq handler for vector" error message that is seen during boot-up. That error message first appeared with BIOS 2010 (AM4 combo V2 PI 1.0.0.1 patch B) and seems to have caused some confusion for some AMD Linux users. Thank you!

https://www.asus.com/us/Motherboards/ROG-Crosshair-VIII-Hero-WI-FI/HelpDesk_BIOS/